It can be difficult to heat a substrate being processed in a substrate processing tool. Variation in substrate heating may lead to within-substrate temperature variations. Such within-substrate temperature variations may lead to within-substrate processing non-uniformities. In some settings, substrates exhibiting such non-uniformities may produce defective devices. Further, deposition product may be deposited in the lower processing chamber, leading to reduced temperatures in the reaction chamber and therefore increased power consumption to overcome the inadequate heating. Additionally, the build-up of deposition product in the chamber can lead to premature chamber cleaning requirements and increased cost.